Modern land combat is expected to become dependent upon airborne surveillance of battlefields to obtain a synoptic picture of the combat theater, locate allied and enemy surface units, and identify surface objects, preferably on a real-time basis. The synoptic picture objective may require a single, integrated ground picture of up to 1 million square kilometers in extent, with surface/cultural features identifiable to an image resolution of 3 meters or less. Identification of surface targets may require scenes of 200 to 300 square kilometers in extent, with image resolution of 1 meter or less. Taken together, these requirements suggest an image display of between about 3×108 to about 1×1011 pixels per frame, which is beyond the capability of current video display technology.
The display format for standard definition television (SDTV) is 480×640 or about 3×105 pixels. High definition television (HDTV) can have display formats with as many as 1,080×1,920 or about 2×106 pixels. Displays of larger images require mosaics of video monitor screens. For example, a 4×5 array of HDTV monitors could display approximately 4×107 pixels. Such mosaics have been constructed, but approximately 150 HDTV screens would be required to meet even the 3×108 pixel display requirement.
Electronic image “zooming” (magnification adjustment) can cover the dynamic range of image scale and lowest-level resolution capability, but not simultaneously in a single image. Magnified high-resolution viewing thus results in a loss of context of a wide-field background image.
High quality photographic emulsions can attain 1,000 line-pairs/millimeter (0.5 micron resolution, which is at or close to the diffraction limit of visible light). A 70 mm motion picture frame (approximately 70 mm×35 mm frame dimensions) would therefore be capable of presenting nearly 1×1010 pixels, projected to the desired degree of magnification. Film-based systems require a process to expose the frame, develop and fix the image, and project the image using filtered light. Although camera systems and film stock developed for aerial reconnaissance can meet or exceed image display requirements for combat theaters, a time delay is associated with their use and there are elaborate processing requirements. Thus, photographic emulsion technology has not been used for real time image recognition technology.